This invention relates to a low voltage buried wire isolator and more particularly to an isolator designed to eliminate a potential fire hazard in telephone and television cable wiring.
In most dwellings, cable television wires, telephone wires, and electrical power wires are mutually grounded to a metal water pipe. The problem associated with the mutual grounding of the television, telephone and electrical wires is that the same provides a zero potential difference for returning electricity to ground. In the event of a power crossover from any of the utilities, the current resulting from the same can damage the telephone or cable television equipment. The power crossover can also cause overheating of the metal sheath surrounding the wire which can lead to spontaneous combustion of the material in contact with the mtal sheath. Such combustion can cause severe damage to the area surrounding the cable.
This condition, power seeking a ground through the telephone or television cable service wire sheaths, will occur in the event of a disruption impairment and/or absence of electrical power bonding of the neutral/ground service link from the structure to the power feed or anywhere within the power feed gradient.
In applicant's copending application, a low voltage buried wire isolator was described which was operatively connected to a conventional signal circuit protector which had been previously installed in or on the existing building structure. The instant invention is designed to combine the low voltage buried wire isolator of the previous invention with a signal circuit protector in a single housing, and which is particularly well-suited for installation on new construction.
It is therefore a principal object of the invention to provide a low voltage buried wire isolator.
A further object of the invention is to provide a low voltage buried wire isolator which interrupts the metallic path presently existing between the common grounding system used in and around structures and the positive grounding system of the telephone and television cable grounding systems.
A further object of the invention is to provide a low voltage buried wire isolator which may be easily installed in existing structures having telephone or television cables extending thereinto.
Yet another object of the invention is to provide a low voltage buried wire isolator including a high voltage protector means therein designed to normally prevent the flow of electrical current therethrough which is below a predetermined value.
Still another object of the invention is to provide an apparatus wherein a low voltage buried wire isolator and a signal circuit protector are combined in a single housing.
Yet another object of the invention is to provide a low voltage buried wire isolator which is economical of manufacture and durable in use.
These and other objects will be apparent to those skilled in the art.